Metal mold



K. A. LINDNER 2,106,614

` Janffzs, 193s.

METAL MOLD Filed Jan. so, 193s 2 sheets-sheetgl' Il Imi' ATTORNEY Patented Jan. 25, 1938 UNITED- l STATE-s PATENT "OFFICE Meur. Mom

Karl A. Lindner,

Baltimore, Md., American Smelting and lte'nin New York, N. Y., .a corporation of New Jersey Application January so, 1936, semi No. 61,449

'This invention relates to metal molds for casting metals and particularly concerns certain improvements in the construction of such molds for inhibiting or preventing deformation 'thereof' in use.

In the production of vertical cast copper' cakes, 1

i for example, it is lcustomary to pour the molten copper into a copper mold provided with a vertlcally disposed cavity and having relatively thick l walls which are cooled by circulating a stream of water through conduits disposed therein. However, notwithstanding the presence ofv the cooling water. the high temperature of the molten copper introduced into the mold causes strains 15 and stresses to be set up in th'e mold walls which, in the case of the ordinary copper mold, exceeds the elastic' limits"of the mold to such an extent.

Athat the mold ultimately becomes so warped or deformed that imperfect cakes result.

20 "In accordance withthepresent invention, it

has been found that the warping or deformation of the mold is minimized by providing open spaces or areasin the mold walls which allow free expansion thereof thus providing relief from the 25 distortional forces accompanying the casting operation. These open-areas also facilitate cooling of the mold and tend to maintain same at lower operating temperatures by reason of the increased surface arca of the mold which they provide.

30 Various other featuresof the invention, which embrace new and original features of construetion. arrangements ofelements and combinations of parts, will be apparent from the f ollowingpar-- ticular description and from an inspection ofthe accompanying drawings.A f

Although the novel features which are believedto becharacterlstic of this invention will belierticlllsrly Pointed out in the claims` appended here- 40 to, the invention itself, as to its objects and 'ad-l vantages, and the manner in Vwhich itmay be a carried out, may be better understood by re ferring to the following description taken in. connection with the drawings forming apart thereof, in which -1"ig. lis a sectional plan' view of one'form of lnventionftaken 5' claims. (ci. cle- 139) Like reference characters .denote like parts in theseveral figures of the drawings.

. Referring more particularly to the drawings, I0 designates generally a relatively thick-walled copper mold comprising two corresponding pieces 5 or halves I2 and Il defining a vertical mold cavity it which is closed at the bottom' by a removable.

-gate I8. Passageways-- 20 communicating with inlets 22 and outlets 2 4 are provided in the mold walls for the circulation of the cooling fluid. In the two-piece mold shown, the two halves, after accurate and true machining'of the abutting surfaces, are held in assembled position by bolts 28 fitted through holes 28: Recesses 30 are provided for securing the assembled mold in the usual cradle.' w A During the castingoperation, the' molten metal induces expansion of the` mold walls which is followed by contraction as the cakes cool and as a result of these-repeated' strains and stress the 20 ordinary mold soon becomes deformed and produces irregularities and imperfections in the cakes.

In casting substantially parallel-sided cakes particular1y,` the warping of the mold may become so pronounced as `to cause the cakesto become lodged in the mold from which they are removed lonly with dimculty.

The present' invention overcomes these disadvantages by insuring freedom of expansion which. it has been found, may be readily provided by- 30 open spaces in the mold wall. These open spaces or areas are shown as vertical slots or grooves 32 -in Figs. 1, land 3, ashorizontal slots or grooves y vIl in Fig. 4; and as both horizontal and vertical 35,

4slots in F18. 5.

The number and spacing of the slots or grooves will vto a large extent depend upon the size of the mold. In 'general the slots may extend to a 4depth of approximately one half theA thickness of the mold wall although a greater or lesser 40 depth maybe provided as desired.

In the moldshown in Figs. 1-3 two slots in either half Foi? the mold body are shown and in a mold for casting a 800 lb. copper cake with a cav- .4%" deep and V4" wide.

In Fig. v4 the mold is shown provided with three horizontal slots extending completely around the vity measuring v12"' x 4%"`x 35" the slots may be 4 mold body, the slots being/ approximately 6%" deep in the ends, and-8'.' deepin the sides. leaving a metal 'thicknessof about 3" between the bottomsof the slots and the mold cavity. A mold of this type withthe 'slots spaced ,at 4". intervals has given excellentfresults in casting u 800 lb. copper cake ina mold with a cavity of 29" x 4 x 22B/2".

In the modified mold shown in Fig. 5, the slots are both vertical and horizontal, three of the former and four of the latter being provided in the particular mold shown in which the depth of the vertical slots is 4%" and that of the horizontal slots 6" on the sides and 61/2" on the ends of the mold.

'I'he speciilc constructions above described are, of course, to be regarded only as illustrative as the invention is capable of embodiment in various other forms and modifications.

From the foregoing description it will be apparent that the invention, in a sense, provides an improved thin-walled mold in that a substantial reduction in thickness of the mold wa'llis effected at intervals while between the intervals of reduction in thickness the requisite reinforcement to prevent deformation of the mold under the weight of the metal cast is present.

While certainfeatures and embodiments of the invention have been described and referred to r in detail for purposes of explanation and illustration, it will be understood vthat it is intended to embrace within the scope of the invention such modifications and changes as may be made by those skilled in the art to adapt it to varying conditions and uses'.

What is lclaimed is:

1. A multiple piece copper mold comprising two side pieces joined together, said side pieces having recessesymachined therein forming a mold cavity having uninterrupted walls, and slots in the outside surfaces only of the side pieces extending to a substantial depth therein to form expansion spaces for the relief of distortional to allow for free expansion of the body for theV relief of distortional strains produced in the metal incident to casting operations.

p 3. A copper mold comprising a body defining a vertical mold cavity therein for producing vertically cast copper cakes, the said body being provided on its outside only with vertically extending slots .or grooves of substantial depth and of suflicient width to allow for free expansion ,of the body for the relief of distortional strains produced in the metal incident to casting operations.

4. A copper mold comprising a body defining a vertical mold cavity therein for producing vertically cast copper cakes, the said body being provided but only on the outside thereof with horizontally extending slots or grooves of substantial depth and of suiiicien't width to allow for free expansion of the body. for the relief of distortional strains produced in the metal incident to casting operations.

5. A copper mold comprising a body enclosing a mold cavity having uninterrupted surfaces, and having intersecting slots o r grooves on its outer surfaces and extending to a substantial depth in the mold body to provide free expansion spaces for accommodating expansion of the mold and alleviating distortional stresses in the mold KARL A. LINDNER. 

